As the highways become more crowded, especially during rush hours, the potential for multi-car accidents increases. Most of this can be attributed to drivers in vehicles not being able to adequately assess how fast the vehicles in front of them are braking. Braking warning devices have been described in the art that provide this capability by a variety of different mechanisms. Many of these devices, however, do not provide the degree of resolution to aptly characterize the severity of braking, and in some cases, are susceptible to the vehicle's attitude (i.e. ascending or descending a hill).